Spring actuated typewriter action with fault sensing means



Oct. 6, 1964 R. SALTO 3,151,722

SPRING ACTUATED TYPEWRITER ACTION WITH FAULT SENSING MEANS Filed Sept. 26, 1965 2 Sheets-Sheet 1 Oct. 6, 1964 R. SALTO 3,151,722

SPRING ACTUATED TYPEWRITER ACTION WITH FAULT SENSING MEANS Filed Sept. 26, 1963 2 Sheets-Sheet 2 United States Patent 3,151,722 SPRING ACTUATED TYPEWRITER ACTION WITH FAULT SENSING MEANS Rinfldo Salto, Ivrea, Italy, assignor to lag. C. Glivetti & C., S.p.A., Ivrea, Italy, a corporation of Italy Filed Sept. 26, 1963, Ser. No. 311,709 Claims priority, application Italy, Sept. 28, 1962, 18,982/ 62 8 Claims. (Cl. 197-17) This invention relates to a power operated typewriter comprising a set of type actions each one connected to an interponent adapted to be coupled with a common reciprocable actuator for the forward stroke thereof and to condition a cyclically operating mechanism for operation at the depression of a corresponding key, and a spring for reciprocating said actuator through said forward stroke, said actuator being restored and said spring being tensioned by said mechanism.

In a known typewriter of the above type the spring of the actuator is strong enough to actuate but one type action and not strong enough to actuate more than one type action, thus preventing the simultaneous operation of two or more type bars. Since the type bars having different printing area require different force of impact, they should be provided with different restoring springs. In this case it is impossible to have an actuating spring strong enough to actuate for example a single type bar having a big printing area and not strong enough to actuate two type bars having a small printing area. Therefore such a known typewriter cannot have the individual restoring spring corresponding to the printing area of the type bar, whereby the print work does not result uniform.

Furthermore, the force of impact cannot be adjusted, for example in order to simultaneously print a number of copies or according to the position of the case shifting device.

The primary object of the invention is to provide a typewriter of the above type adapted to produce a uniform print work.

Another object is to provide a typewriter wherein the simultaneous impact of more than one type bar is prevented.

Another object is to provide a typewriter wherein the force of the impact is individually adjustable according to the printing area of the character.

Still another object is to provide a typewriter wherein the force of the impact of all type bars is simultaneously adjustable both manually and automatically under the control of the case shift device.

A further object is to provide a typewriter wherein the shock of the common actuator against the coupled interponent is prevented.

With the above object in view, in a power operated typewriter having a cyclically operating mechanism, a set of type actions, a set of keys associated with said type actions, and a common reciprocable actuator for said type actions, I now provide a set of interponents each one connected to one of said type actions, each one of said interponents at the depression of the associated key being adapted to be coupled with said actuator for the forward stroke thereof and to condition said mechanism for operation, a tensioned spring conditionable for reciprocating said actuator through said forward stroke at a predetermined speed in the case a single interponent has been coupled therewith and at reduced speed in the case more than one interponent has been coupled therewith, control means normally locking said actuator at rest against the urge of said spring, said control means being operable by said mechanism at the beginning of a machine cycle for conditioning said spring and at the end of said cycle for 3,151,722 Patented Oct. 6, 1964 ice restoring said actuator, and a locking element operable by said mechanism at an invariable speed and adapted to be inserted at a predetermined instant on the path of the forward stroke of said actuator to intercept said actuator in the case said forward stroke is effected at said reduced speed.

Other objects, features and advantages of the invention will become apparent from the following detailed description of a preferred embodiment thereof, made with reference to the accompanying drawings, wherein:

FIG. 1 is a right-hand partial longitudinal sectional view of a typewriter according to the invention;

FIG. 2 is another right-hand partial longitudinal sectional view of the machine;

FIG. 3 is a third right-hand partial longitudinal sectional view of the machine;

FIG. 4 is a partial plan view of the machine;

FIG. 5 is a right-hand longitudinal view of a detail of FIG. 2 in an operated position.

With reference to FIG. 1, the typewriter comprises a set of type actions each one having a type bar 7 pivoted on a circular pivot 8 carried by the usual type bar segment 9 and adapted to strike against a platen 6. Each type bar 7 is connected through a link 11 to a movable intermediate element or lever 12 fulcrumed at 13 and provided with an indented slot 14. A restoring spring 16 may be anchored at the slot 14 in a variable position in order to individually adjust the force of the impact according to the printing area of the type mounted on the type bar 7.

Fulcrumed at 18 on each lever 12 is an interponent 19 having a projection 21 normally latched by a shoulder 22 of a latch 23 fulcrumed at 24 on the lever 12 and connected to the interponent 19 by a spring 26. The latch 23 is provided with a bent lug 27 adapted to cooperate with a lever 28 fulcrumed at 29 on a key lever 31.

Each interponent 19 is provided with a tooth 32 by means of which may be coupled with a common reciprocable actuator formed of a universal bar 33 (-see also FIG. 4) fulcrumed at 34. An arm 36 (FIG. 1) of the bar 33 is urged counterclockwise by a tensioned spring 37 conditionable for reciprocating the actuator 33 through the forward stroke thereof at a predetermined speed in the case a single interponent 19 has been coupled therewith and at reduced speed in the case more than one interponent has been coupled therewith. The arm 36 is further connected through a link 38 to control means normally locking the actuator 33 at rest against the urge of said spring, said control means comprising a lever 39 fulcrumed at 41.

The lever 39 is provided with a roller 42 normally urged by the spring 37 to contact a cam member 43 secured to a cyclically operating mechanism comprising a sleeve 44 adapted to be conditioned for operation by each interponent at the depression of the corresponding key lever 31. More particularly, a universal bar 46 pivoted at 47 is urged clockwise by its weight to contact the interponents 19. An arm 49 of the bar 46 is connected through a link 51 to an arm 52 of a bail 53 fulcrumed at 54. A normally latched cycle conditioning element formed of a lever 58 fulcrurned at 59 is provided with a lug 57 normally latched by a second arm 56 of the bail 53. In fact a spring 61 urges the lever 58 to engage with the lug 57 the upper edge of the arm 56. A second lug 62 of the lever 58 is normally located on the path of a projection 63 of each one of three clutch teeth 64 fulcrumed on three pivots 66 of the cam 43. The teeth are mutually spaced apart of degrees, and are mutually connected by a ring 67 connected in turn to the cam 43 by means of a spring 68.

The teeth 64 are adapted to engage a clutch ratchet wheel 69 secured to a shaft 70 continuously rotated in a manner known per se by the conventional electric motor not shown in the drawings, this clutch ratchet wheel 69 is adapted to be engaged by the teeth 64 for one cycle of 120 degrees, whereby the cam 43 and all other cams secured to the sleeve 44 are formed with three equal lobes. It is to be noted that each lobe of the cam 43 comprises a first portion 111 (FIG. 2) adapted to cause said actuator to be moved at a controlled speed until contacting the coupled interponent 19, a second portion 129 adapted to condition the spring 37, and a third portion 130 adapted to restore the actuator 33.

A lever 72 fulcrumed at 73 is normally urged by a spring 74 to contact a second cam 71 secured to the sleeve 44. The lever 72 is adapted to effect, in a manner known per se, various machine functions, as for example the ribbon vibrating and feeding. The lever 72 is connected through a link 76 to means reciprocable by the mechanisms 44 at an invariable speed, said means comprising a lever 77 fulcrumed at 78. Another lever 79 fulcrumed at 78 is urged by a spring 81 to contact a pin 82 of the lever 77 and is provided with a locking element adapted to be inserted on the path of the forward stroke of the common actuator 33 to intercept said actuator in the case said forward stroke is efiected at reduced speed. More particularly, said locking element is formed of a projection 83 of the lever 79 and is adapted to be inserted on the path of lug 84 bent from the arm 36 of the universal bar 33.

A lever 89 fulcrumed at 73 is normally urged by a spring 88 to contact a pin 87 of the lever 72 and is provided with a lug 91 adapted to cooperate with an arm 92 of the bail- 53. The lever 58 is provided with an arm 93 adapted to cooperate with a third cam 94 secured to the sleeve 44, but since its lug 57 normally contacts the arm 56 of the bail 53, the arm 93 is normally distanced from the cam 94. The lug 57 of the lever 58 is normally frontally contacted by a normally ineffective latching member formed of a tooth 96 of a bail 97 fulcrurned at 54 and urged by a spring 98 connected to an arm 102 and for causing all the coupled interponents 19 to berelatched by their latches 23 in the case the actuator 33 has been intercepted. More particularly, said device comprises a lug 103 (FIG. 3) of a lever 104 fulcrumed at 73 and adapted to cooperate with the arm 102 of the bail 97. The lever 104 is normally urged by a spring 105 to contact a cam 106 adapted to be rotated for one revolution by the shaft 70, through a clutch generically indicated by the numeral 107 and controlled in a manner known per se by a suitable key not shown. The lever 104 is connected through a link 108 to an arm of a bail 109 fulcrumed at 47, and havinga crossbar 110 embracing all the interponents 19 (FIG. 4).

The typewriter operates as follows:

At the depression of a key lever 31 (FIG. 1), the lever 28 rocks the latch23 clockwise thus unlatching the corresponding interponent 19, which is now rotated counterclockwise by the spring 26. The interponent 19 on one hand through its tooth 32 is coupled with the universal bar 33 (position dotted in FIG. 1), on the other hand it rocks counterclockwise the universal bar 46 This bar through the link 51 rocks counterclockwise the bail 53, whosearm 56 unlatches the lug 57; The lever 58 is now rocked counterclockwise by the spring 61 and on one hand contacts with its arm 93 (FIG. 2) the cam 94, on the other hand disengages its lug 62 (FIG. 1) from the projection 63 of the clutch tooth 64 contacting same. The spring 68 through the ring 67 rocks the three teeth 64 counterclockwise on the respective pivots 66, engaging them 4 with the wheel 69, whereby the clutch 64, 69 is engaged and the sleeve 44 together with the earns 43, 71 and 94 (FIG. 2) is rotated for a machine cycle.

At the beginning of the cycle the slightly descending portion 111 of the cam 43 (FIG. 1) causes the lever 39 to be rocked clockwise, together with the bar 33, by the urge of the spring 37 at a controlled speed. This rocking movement causes the universal bar 33 to contact the tooth 32 of the coupled interponent 19, substantially, without shock. Subsequently the portion 129 of the cam 43 releases the roller 42 of the lever 39, whereby the spring 37 causes the universal bar 33 to be rocked counterclockwise and to effect the forward stroke at a predetermined speed depending only from the tension of the spring 37 and of the spring 16 of the type action to be actuated. In fact, due to the speed of the cam 43, the spring 37 is unable to maintain the roller 42 in contact with the portion 129 (FIG. 2) of the cam 43, whereby the speed of the bar 33 is not controlled by said portion.

The bar 33 in turn actuates the type action by moving forward, (leftwards in FIG. 1) the interponent 19, which rocks the lever 12 counterclockwise and through the link 11 causes the type lever 7 to strike against the platen 6. Obviously as it is known, the bar 33 moves the type lever 7 only for a portion of the stroke of this latter, the remaining portion being effected by the inertia of the type action. During the movement of the universal bar 33, the interponent 19 is rocked clockwise about the pin 18, whereby at the end of the forward stroke it is automatically relatched by the latch 23.

While the cam 43 rocks the universal bar 33 counterclockwise, the cam 94 (FIG. 2) engages the arm 93, whereby the lever 58 is rocked counterclockwise thus locating the lug 62 (FIG. 1) again on the path of the projection 63 of the next following tooth 64. Therefore, the sleeve 44 will be arrested at the end of the cycle of degrees. In turn, the lug 57 of the lever 58 is temporarily located above the arm 56 of the bail 53 and disengages the tooth 96 (FIG. 2). The bail 97 is now rocked by urge of the spring 98 and locates the tooth 96 under. the lug 57.

During the counterclockwise rotation of the universal bar 33, the cam 71 rocks counterclockwise the lever 72. The pin 87 of the lever 72 releases the lever 89 which is urged by the spring 88 to engage through the lug 91 the arm 92 of the bail 53. This bail is thus rocked clockwise and on one hand locates its arm 56 under the lug 57 of the lever 58, on the other hand, through the link 51 (FIG. 1), restores the universal bar 46. Subsequently the cam 94 (FIG. 2)v releases the arm 93, whereby the lug 57 of the lever 58 remains latched by the upper edge of tooth 96. When the universal bar 33 reaches the end of its forward stroke, the stud 101 of the lever 39 engages the arm 99 of the bail 97, whereby the tooth 96 releases the lug 57. This lug may now contact the arm 56 of the bail 53 thus returning in its initial position.

The lever 72 during its counterclockwise rotation, through the link 76, rocks the lever 77 at an invariable speed. The lever 77 is followed by the lever 79 which at a predetermined instant from the beginning of the cycle inserts the projection 83 on the path of the forward stroke of the lug 84. In the present case, since a single interponent 19 has been coupled with the universalbar 33, this bar is rocked at the. predetermined speed and locates the lug 84 on the path of the projection 83 of the lever 79 before the lever 77 is entirely rocked, whereby the lever 79 is arrested by the lug 84 in the position dotted in FIG. 2 and does not affect the universal bar 33.

After the impact of the type bar, the portion 130 of the cam 43 rocks counterclockwise the lever 39, which through the. link 38 restores the universal bar 33 and tensions the spring 37 (FIG. 1). The sleeve 44 is now arrested through its next following tooth 64 by the lug 62 of the lever 58 after 120 degrees of rotation. In turn the type action is restored by the spring 16.

If a second key is depressed before the end of the cycle started by a first key, when the universal bar 33 is already rocked counterclockwise, the interponent 19 of the second key locates its tooth 32 behind the bar 33 (rightwards in FIG. 1). During its restoring stroke the bar 33 engages now the edge 112 of the interponent 19 of the second key, and rocks same partially clockwise. The intemonent 19 is thus caused to be coupled with the bar 33 Without being relatched by the latch 23. Therefore, at the end of the cycle of the first key, the sleeve 44 is not arrested and begins immediately the second cycle relating to the second depressed key.

On the contrary, if the second key is depressed so early after the first one, as the universal bar 33 substantially has not been rocked, and particularly if two or more keys are simultaneously depressed, tWo or more interponents 19 are simultaneously coupled with the bar 33. In this case the spring 37 reciprocates the universal bar 33 through a forward stroke at a substantially reduced speed. However, the lever 79 is moved by the cam 71, through the lever 72, the link 76, the lever 77 and the spring 81, at an invariable speed, independent of the number of the interponents 19 engaged by the bar 33. The projection 83 of the lever 79 is now inserted on the path of the forward stroke of the lug 84 before the arrival of the lug 84, which is thus intercepted by the projection 83, whereby the bar 33 is arrested in the position of FIG. 5.

The type bars 7 corresponding to the interponents 19 engaged by the bar 33 do not reach the platen 6, whereby their overlapping is prevented. Furthermore, the stud 101 (FIG. 2) of the lever 39 does not reach the arm 99 of the bail 97, which remains thus with the tooth 96 under the lug 57 of the lever 58. The cycle of the cam 43 is now completed, but at the end thereof the latching member 95 is not rendered ineffective and the lever 58 is unable to engage the clutch 64, 69 at the depression of other keys, whereby the typewriter remains locked.

To release the typewriter so locked, all the coupled interponents 19 need to be relatched by their latches 23, by means of the above described manually controlled device. By depressing the key controlling said device, the clutch 197 (FIG. 3) is engaged and causes the cam 106 to effect a cycle of 360 degrees. This cam rocks now counterclockwise the lever 104 together with the bail 109, whereby the cross-bar 110 engages the coupled interponents and causes them to be relatched by their latches 23. Near the end of its stroke the lever 104 through its lug 1G3 engages the arm 192 of the bail 97 and disengages the tooth 96 from the lug 57 of the lever 58. The latching members 96 are thus rendered ineffective and the lug 57 is restored by the spring 61 to contact the arm 56.

The force of impact of all the type actions may be simultaneously adjusted by altering the tension of the spring 37 within two extreme predetermined values. In this order the rearward end of the spring 37 is anchored to a lever 113 fulcrumed on a pivot 114 of a bail 115. The lever 113 may be located in different positions by means of a positioning lever 116 manually operable in a known manner. The lever 116 through a pin 117 cooperates with a toothed edge 118 of the lever 113.

Furthermore, the force of impact of all the type actions may be automatically adjusted by the conventional case shifting device in a manner as to alter the tension of the spring according to values corresponding to the positions of said case shifting device, the last named values being comprised within the above named extreme values. More particularly, said case shifting device comprises a bail 124 fulcrumed at 126 and connected by a pin 127 to a projection 128 of the type bar segment 9. The bail 115 is pivoted on a shaft 121 and is provided with a projection 122 normally contacting a pin 123 of the bail 124. \Vhen the segment 9 is lowered in its upper case position in a manner known per se, the bail 124 is rocked counterclockwise and rocks the bail 115 clockwise. The

lever 113 is now rocked counterclockwise about the pin 117, thus increasing the tension of the spring 37.

It will be understood that the actuator 33 and the element 83 are designed for enabling the actuator 33 to arrest the element 83 in the case the forward stroke is effected substantially at a predetermined speed and to be arrested by said element in the case said forward stroke is effected at a substantially reduced speed irrespective of the initial tension of the spring 37 within said extreme values.

It is intended that many changes, modifications, improvements and additions of parts may be made to the described typewriters without departing from the scope of the invention.

What I claim is:

1. In a power operated typewriter having a cyclically operating mechanism, a set of type actions, a set of keys associated with said type actions, and a common reciprocable actuator for said type actions, the combination comprising:

(a) a set of interponents each one connected to one of said type actions, each one of said interponents at the depression of the associated key being adapted to be coupled with said actuator for the forward stroke thereof and to condition said mechanism for operation,

(b) a tensioned spring conditionable for reciprocating said actuator through said forward stroke at a predetermined speed in the case a single interponent has been coupled therewith and at reduced speed in the case more than one interponent has been coupled therewith,

(0) control means normally locking said actuator at rest against the urge of said spring, said control means being operable by said mechanism at the beginning of a machine cycle for conditioning said spring and at the end of said cycle for restoring said actuator,

(d and a locking element operable by said mechanism at an invariable speed and adapted to be inserted at a predetermined instant on the path of the forward stroke of said actuator to intercept said actuator in the case said forward stroke is efiected at said reduced speed.

2. In a power operated typewriter having a cyclically operating mechanism, a set of type actions, a set of keys associated with said type actions, and a common reciprocable actuator for said type actions, the combination comprising:

' (a) a set of interponents each one connected to one of said type actions, each one of said interponents at the depression of the associated key being adapted to be coupled with said actuator for the forward stroke thereof and to condition said mechanism for operation,

(1)) a tensioned spring conditionable for reciprocating said actuator through said forward stroke at a predetermined speed in the case a single interponent has been coupled therewith and at reduced speed in the case more than one interponent has been coupled therewith,

(0) control means normally locking said actuator at rest against the urge of said spring, said control means being operable by said mechanism at the beginning of a machine cycle for conditioning said spring and at the end of said cycle for restoring said actuator,

(d) means reciprocable by said mechanism at an invariable speed,

(e) and a locking element yieldably connected to said reciprocable means and adapted to be inserted at a predetermined instant on the path of the forward stroke of said actuator, said actuator being adapted to arrest said element in the case said forward stroke is effected at said predetermined speed and to be arrested by said element in the case said forward stroke is effected at said reduced speed.

3. In a power operated typewriter having a cyclically operating mechanism, a set of type actions, a set of keys associated with said type actions, and a common reciprocable actuator for said type actions, the combination comprising:

(a) a set of interponents each one connected to one of said type actions, each one of said interponents at the depression of the associated key being adapted to be coupled with said actuator during the forward stroke thereof,

(b) a normally latched cycle conditoning element adapted to be unlatched for conditioning said mechanism for operation,

(c) means normally effective for latching said cycle conditioning element and adapted to be rendered ineffective by each interponent when so coupled,

(d) a tensioned spring conditionable for reciprocating said actuator through said forward stroke at a predetermined speed in the case a single interponent has been coupled therewith and at reduced speed in the case more than one interponent has been coupled therewith,

(e) control means normally locking said actuator at rest against the urge of said spring, said control means being operable by said mechanism at the beginning of a machine cycle for conditioning said spring and at the end of said cycle for restoring said actuator,

(f) a locking element operable by said mechanism at an invariable speed and adapted to be inserted at a predetermined instant on the path of the forward stroke of said actuator to intercept said actuator in the case said forward stroke is effected at said reduced speed,

(g) a normally ineffective latching member adapted to be rendered elfective by said mechanism at the beginning of said cycle for latching said cycle conditioning element irrespective of said latching means,

(h) and an element connected to said actuator and adapted to render said latching member ineffective at the end of saidforward stroke in the case said actuator has not been intercepted.

4. In a power operated typewriter having a cyclically operating mechanism, a set of type actions, a set of keys associated with said type actions, and a common reciprocable actuator for said type actions, the combination comprising:

(a) a set of interponents each one connected to one of said type actions, each one of said interponents at the depression of the assocaited key being adapted to be coupled with said actuator during the forward stroke thereof,

(b) a normally latched cycle conditioning element adapted to be unlatched for conditioning said mechanism for operation,

() means normally eifective for latching said cycle conditioning element and adapted to be rendered ineffective by each interponent when so coupled,

(d) a tensioned spring conditionable for reciprocating said actuator through said forward stroke at a predetermined speed in the case a single interponent has been coupled therewith and at reduced speed in the case more than one interponent has been coupled therewith,

(e) control means normally locking said actuator at rest against the urge of said spring, said control means being operable by said mechanism at the beginning of a machine cycle for conditioning said spring and at the end of said cycle for restoring said actuator,

(f) a locking element operable by said mechanism at an invariable speed and adapted to be inserted at a predetermined instant on the path of the forward stroke of said actuator to intercept said actuator in the case said forward stroke is effected at said reduced speed,

(g) a normally ineffective latching member adapted to be rendered effective by said mechanism at the beginning of said cycle for latching said cycle conditioning element irrespective of said latching means,

(h) an element connected to said actuator and adapted to render said latching member ineffective at the end of said forward stroke in the case said actuator has not been intercepted,

(i) and a manually controlled device for rendering said latching member ineffective in the'case said actuator has been intercepted.

5. In a power operated typewriter having a cyclically operating mechanism, a set of type actions each one comprising a movable intermediate element, a set of keys associated with said type actions, and a common reciprocable actuator for actuating said type actions through the proper intermediate element, the combination comprising:

(a) a normally latched interponent pivoted on each intermediate element, said interponent when unlatched being adapted to be coupled with said actuator for the forward stroke thereof and to condition said mechanism for operation,

(b) a latch pivoted on said intermediate element and normally latching said interponent, said latch being operated at the depression of the associated key for unlatching said interponent,

(c) a tensioned spring conditionable for reciprocating said actuator through said forward stroke at a predetermined speed in the case a single interponent has been coupled therewith, and at reduced speed in the case more than one interponent has been coupled therewith,

(d) control means normally locking said actuator at rest against the urge of said spring, said control means being operable by said mechanism at the beginning of a machine cycle for conditioning said spring and at the end of said cycle for restoring said actuator,

(e) a locking element operable by said mechanism at an invariable speed and adapted to be inserted at a predetermined instant on the path of the forward stroke of said actuator to intercept said actuator in the case said forward stroke is effected at said reduced speed,

(f) and means for mounting said actuator in such a manner as to cause said coupled interponent to be relatched by said latch at the end of said forward stroke in the case said actuator has not been intercepted.

6. In a power operated typewriter having a cyclically operating mechanism, a set of type actions each one comprising a movable intermediate element, a set of keys associated with said type actions, and a common reciprocable actuator for actuating said type actions through the proper intermediate element, the combination comprising:

(a) a normally latched interponent pivoted on each intermediate element, said interponent when unlatched being adapted to be coupled with said actuator for the forward stroke thereof,

(b) a latch pivoted on said intermediate element and normally latching said interponent, said latch being operated at the depression of the associated key for unlatching said interponent,

(c) a normally latched cycle conditioning element adapted to be unlatched for conditioning said mechanism for operation,

(d) means normally effective for latching said cycle conditioning element and adapted to be rendered ineffective by each interponent when so coupled,

(e) a tensioned spring conditionable for reciprocating said actuator through said forward stroke at a predetermined speed in the case a single interponent has been coupled therewith, and at reduced speed in the 9 case more than one interponent has been coupled therewith,

(f) control means normally locking said actuator at rest against the urge of said spring, said control means being operable by said mechanism at the beginning of a machine cycle for conditioning said spring and at the end of said cycle for restoring said actuator,

(g) a locking element operable by said mechanism at an invariable speed and adapted to be inserted at a predetermined instant on the path of the forward stroke of said actuator to intercept said actuator in the case said forward stroke is effected at said reduced speed,

(It) means for mounting said actuator in such a manner as to cause said coupled interponent to be relatched by said latch at the end of said forward stroke in the case said actuator has not been intercepted;

(i) a normally ineffective latching member adapted to be rendered effective by said mechanism at the beginning of said cycle for latching said cycle conditioning element irrespective of said latching means,

(I) an element connected to said actuator and adapted to disable said latching member at the end of said forward stroke in the case said actuator has not been intercepted,

(m) and a manually controlled device for rendering said latching member ineffective and causing all the coupled interponents to be relatched by their latches in the case said actuator has been intercepted.

7. In a power operated typewriter having a cyclically operating mechanism, a set of type actions, a set of keys associated with said type actions, and a common ICClPIO- cable actuator for said type actions, the combination comprising:

(a) a set of interponents each one connected to one of said type actions, each one of said interponents at the depression of the associated key being adapted to be coupled with said actuator for the forward stroke thereof and to condition said mechanism for operation,

(b) a tensioned spring conditionable for reciprocating said actuator through said forward stroke at a predetermined speed in the case a single interponent has been coupled therewith and at reduced speed in the case more than one interponent has been coupled therewith,

(c) control means normally locking said actuator at rest against the urge of said spring,

(d) a cam member on said mechanism for controlling said locking means, a first portion of said cam member being adapted to cause said actuator to be moved at a controlled speed until contacting the coupled interponent, a second portion of said cam member being adapted to condition said spring without controlling the speed of said actuator, a third portion of said cam member being adapted to restore said actuator,

16 (e) and a locking element operable by said mechanism at an invariable speed and adapted to be inserted at a predetermined instant on the path of the forward stroke of said actuator to intercept said actuator in the case said forward stroke is efiected at said reduced speed.

8. In a power operated typewriter having a cyclically operating mechanism, a set of type actions, a set of keys associated with said type actions, a case shift device, and a common reciprocable actuator for said type actions, the combination comprising:

(a) a set of interponents each one connected to one of said type actions, each one of said interponents at the depression of the associated key being adapted to be coupled with said actuator for the forward stroke thereof and to condition said mechanism for operation,

(1)) a spring tensioned between said actuator and a tension adjusting member and conditionable for reciprocating said actuator through said forward stroke at a substantially predetermined speed in the case a single interponent has been coupled therewith and at substantially reduced speed in the case more than one interponent has been coupled therewith, said member being manually adjustable to alter the tension of said spring within two extreme values,

(c) means for mounting said adjusting member and connected to said case shifting device in a manner as to alter the tension of said spring according to values corresponding to the positions of said device, the last named values being comprised within said extreme values,

(d) control means normally locking said actuator at rest against the urge of said spring, said control means being operable by said mechanism at the beginning of a machine cycle for conditioning said spring and at the end of said cycle for restoring said actuator,

(e) means reciprocable by said mechanism at an invariable speed,

(f) and an element yieldably connected to said reciprocable means and adapted to be inserted at a predetermined instant on the path of the forward stroke of said actuator, said actuator being adapted to arrest said element in the case said forward stroke is effected at said substantially predetermined speed and to be arrested by said element in the case said forward stroke is effected at said substantially reduced speed irrespective of the initial tension of said spring within said extreme values.

References Cited in the file of this patent UNITED STATES PATENTS 1,455,112 Crawley May 15, 1923 2,353,860 Walker July 18, 1944 2,383,256 Kittel Aug. 21, 1945 2,403,270 Eddy July 2, 1946 3,017,978 Schulz Jan. 23, 1962 

1. IN A POWER OPERATED TYPEWRITER HAVING A CYCLICALLY OPERATING MECHANISM, A SET OF TYPE ACTIONS, A SET OF KEYS ASSOCIATED WITH SAID TYPE ACTIONS, AND A COMMON RECIPROCABLE ACTUATOR FOR SAID TYPE ACTIONS, THE COMBINATION COMPRISING: (A) A SET OF INTERPONENTS EACH ONE CONNECTED TO ONE OF SAID TYPE ACTIONS, EACH ONE OF SAID INTERPONENTS AT THE DEPRESSION OF THE ASSOCIATED KEY BEING ADAPTED TO BE COUPLED WITH SAID ACTUATOR FOR THE FORWARD STROKE THEREOF AND TO CONDITION SAID MECHANISM FOR OPERATION, (B) A TENSIONED SPRING CONDITIONABLE FOR RECIPROCATING SAID ACTUATOR THROUGH SAID FORWARD STROKE AT A PREDETERMINED SPEED IN THE CASE A SINGLE INTERPONENT HAS BEEN COUPLED THEREWITH AND AT REDUCED SPEED IN THE CASE MORE THAN ONE INTERPONENT HAS BEEN COUPLED THEREWITH, (C) CONTROL MEANS NORMALLY LOCKING SAID ACTUATOR AT REST AGAINST THE URGE OF SAID SPRING, SAID CONTROL MEANS BEING OPERABLE BY SAID MECHANISM AT THE BEGINNING OF A MACHINE CYCLE FOR CONDITIONING SAID SPRING AND AT THE END OF SAID CYCLE FOR RESTORING SAID ACTUATOR, (D) AND A LOCKING ELEMENT OPERABLE BY SAID MECHANISM AT AN INVARIABLE SPEED AND ADAPTED TO BE INSERTED AT A PREDETERMINED INSTANT ON THE PATH OF THE FORWARD STROKE OF SAID ACTUATOR TO INTERCEPT SAID ACTUATOR IN THE CASE SAID FORWARD STROKE IS EFFECTED AT SAID REDUCED SPEED. 